For security reasons you don’t want to be dependent on shipping a large % of your energy between countries. Some examples, Middle East wars over oil as disruptions would cripple world economy. EU dependence on Russian gas pipe line. Local production is more robust as well, not as affected by a failure of a large source of energy. Wind solar battery growth makes sense. Ideally we would add some thorium reactors (cheaper) for use cases where weather cycles leave gaps in power coverage (batteries are ok for short bursts of power but to expensive for long term, example shifting summer production to winter use) . As solar price performance improves and as consumers shift to electric heat pumps etc more homes can cost justify home solar. Over time the optimal mix of energy sources will sort it self out.
By the way solar cells don’t perform well in high temperatures so the optimal location might not be as obvious as this article suggests.
Having said that, there is a place for more efficient high voltage DC transmission, as a part of optimal energy generation and transmission.